This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The P50 Center for Interdisciplinary Research on Nicotine Addiction (CIRNA) includes a highly interactive set of projects and cores focused on tobacco addiction and its treatment. Project 3 uses human neuroimaging to examine the neural substrates of early abstinence symptoms and medication response.